Evidence suggests that industrial trans fatty acids (iTFA) impair lipid profiles while ruminant trans fatty acids (rTFA) may lower insulin resistance and blood pressure. The objective of this article was to determine if the plasma phospholipid percentage of rTFA is associated with a favorable cardiometabolic profile. We collected fasting blood samples from 200 individuals from Quebec city (QC, Canada) aged from 18 to 55 years old, including 100 obese (BMI >/= 30 kg m-2) and 100 non-obese (BMI < 30 kg m-2) men and women. Fatty acid levels in plasma phospholipids were determined using gas chromatography. After separating the subjects into two groups, according to the median percentage of rTFA in plasma phospholipids, participants in the group with higher percentages of rTFA (0.86 +/- 0.24 %) had higher adiponectin levels (p = 0.01) and a lower blood pressure (systolic, p = 0.005; diastolic, p = 0.04). In contrast, concentrations in plasma phospholipids of elaidic acid, a major iTFA, are positively correlated with glycemia in non-obese subjects (p = 0.01) and with both triacylglycerol (TAG) (p = 0.0007) and total cholesterol (TC) (p = 0.009) in obese subjects. These data suggest that rTFA may have beneficial effects on cardiometabolic risk factors conversely to their counterpart iTFA. Dietary sources of TFA should be taken into account in future cardiometabolic studies.